Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
van hanh » van thanh, ban hanh, van anh
cua tre » cua te, cuu tre, cua triet
duc van » duc va, duc tan, duc manh
nang xa » nang x, lang xa, nang ma
cac duc » cac du, cao duc, cac dac
long ha » dong ha, cong ha, dong hoa
van cac » van hac, van cau, van bac
vi cua » vai cua, di cua
te cao » te bao
te san » te ban, ke san, tu san

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: ((te cao) or (te san)) ky ((nang xa) or (long ha)) hoi. hieu van cac duc van hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te cao) OR (te san)) ky ((nang xa) OR (long ha)) hoi. hieu van cac duc van hanh vi cua tre.
• Adding a wildcard symbol may retrieve word variants: ((te cao) or (te san)) ky ((nang xa) or (long ha)) hoi. hieu van cac duc van hanh vi cua tre*.